Some molecules or particles are too large or too hydrophilic to pass through a lipid bilayer. Other molecules could pass through the bilayer but must be transported rapidly in such large numbers that channel-type transport is impractical.
Vanna White Has the World's Most G-Rated Wardrobe Malfunction on 'Wheel of Fortune'. by 11:56 AM PST, December 11, 2015. Playing Vanna White Has the World's Most G-Rated Wardrobe Malfunction on 'Wheel of Fortune'. Vanna White found herself in a sticky situation during Thursday's Wheel of Fortune. While walking across the stage, the hostess, unbeknownst to her, brought part of the set with her when a prop gift got caught on the bottom of her dress.
I put the coin in the machine and pulled the lever. 2. 'motor'. When a machine operates by electricity, you refer to the part of the machine that converts power into movement as the motor. ...a malfunctioning fan motor in the attic space of the building. 3. 'engine'. You do not use 'machine' to refer to the part of a vehicle that provides the power that makes the vehicle move. This part of a car, bus, lorry, or plane is usually called the engine. He couldn't get his engine started. The starboard engines were already running.